Years ago the free-to-play game Fallout Shelter was released. It is still one of the most appreciated mobile games nowadays.
The game is based on one of the fantasies from the Fallout series, but, and this is very important, not the central one. The fantasy of the shelters where people take refuge after the atomic apocalypse. A great idea!
In my humble opinion, the best way to use an AAA game’s IP to create a mobile game is not to transfer the original experience to the closest genre there. That’s the way to infuriate the fanbase, actually.
The best way is to find a marginal but recognizable fantasy. A few examples that come to mind:
Horizon: the fantasy of the tribes with their clothes and their colors. A doll dressing game?
Red Dead Redemption: the fantasy of poor towns with their vices. Maybe a dating sim?
I could go on for hours.
Keep always in mind that free-to-play mobile is essentially entertainment. Don’t think about using IP to make more money, think about expanding it.
(I admit this is hard to accept)